JP5484521B2 - Filter device - Google Patents

Description

The present invention relates to a filter device comprising a filter element for filtering the air, and a Haujin grayed for such filter elements.

Filter elements are used for fluid flow or filtration of gaseous media. For example, a filter element is used to filter the air flow directed into the passenger compartment of the vehicle. For this purpose, the filter element can be used to remove health harmful substances, odors, etc. from the ambient air, especially in air conditioning equipment mounted on automobiles. Examples of such filter elements are particle filters, odor filters or combinations thereof. A further field of use of filter elements is air filters that remove suspended particles from the air supplied to an internal combustion engine. Generally, such air filters have a housing in which a replaceable air filter element is provided.

U.S. Patent No. 6,057,836 discloses an air filter device that includes a filter housing having a number of vertically arranged rods at the bottom thereof. The filter elements can be pressed into the rods and the filter housing can be closed with a cover. This cover is threaded by a butterfly bolt that extends to the bottom of the filter housing. Therefore, the cover can be removed simply by releasing the butterfly bolt, and the filter element can be replaced by hand, so that no additional tools are required. can do. However, it is often desirable that such a simple replacement without tools be practically impossible, because the filter element is replaced in an inappropriate manner by the consumer or using the wrong filter element. This is because there is a risk. As a result, the filtration function may become insufficient, or the wear of the filter material may be accelerated.

(Patent Document 2) discloses an air filter device including two cup-type housing shells that are detachably coupled to each other, wherein the lower shell of the shells is a cone integrated therewith. Having a shaped support pipe. A conical round filter element is press fitted onto the support pipe, and then the upper housing shell is placed on the lower housing shell and screwed to one end of the support pipe. In this air filter, the housing shells are screwed together and can therefore not be released without tools, but since the screw connection can be realized by a screwdriver, again there is a risk of improper replacement of the filter element. Yes, with the aforementioned drawbacks.

U.S. Pat. No. 4,588,426 International Publication No. 00/56423 A1 Pamphlet

The object of the present invention is therefore that the construction is simple and can be manufactured easily and at the same time the filter element housed in the filter housing cannot be replaced or is difficult to replace without tools, in particular special tools. A filter device comprising an improved air filter element and a filter housing for such a filter element is provided.

This object is solved by an air filter device (40) having the features of claim 1 below .
That is, the present invention relates to an air filter element (10) formed by surrounding an outer surface of a cylindrical central tube (11) with a filter material (12), an upper housing part (20b), and the upper housing part (20b). A filter housing (20) for housing the air filter element (10), including a bottom housing part (20a) removably coupled to the air filter element, and an outer periphery of the air filter element (10). The air permeable cylindrical air filter element support body (21) and the central pipe (11) are provided at one end in the cylinder axial direction, and torque is applied to the air filter element (10) from a specially designed special tool. A torque transmitting portion (18) for transmitting and the other end of the central tube (11); And a fastening portion (14, 29) for detachably installing the nozzle (10) on the cylindrical air filter element support body (21) only by an insertion operation or by an insertion and rotation operation. Device (40).

Therefore, the filter device (40) provides an air filter element including a cylindrical center tube (center tube) , where torque transmission for transmitting torque from the tool to the air filter element is provided at one end of the center tube. And a fastening mechanism for detachably mounting the filter element to an air permeable cylindrical support body (referred to as a support tube) by only an insertion operation or an insertion and rotation operation at the other end of the central tube. Is done.

Examples of coupling with only insertion or insertion and rotation are screw coupling, bayonet coupling, locking coupling and / or snap coupling. The advantage of only insertion movement or insertion and rotation movement coupling compared to insertion / locking coupling is that it is difficult to release even when subjected to vibration, especially in trucks, construction machinery, farm equipment, etc. It is advantageous to use. The installed air filter element is accommodated in the support body, and therefore the outer periphery thereof is covered by the support body, so that it cannot be removed from the support body by hand or the removal is always difficult. In this way, the support body can also provide mechanical protection of the filter element, especially with respect to breakage. This is especially the case with portable devices where it is not always certain that the device will be placed in a stable position during filter replacement and therefore the filter element may be damaged if the device is dropped on the ground with the filter housing open. Can be important in relation to other devices. By combining with the torque transmission part of the fastening means, a filter device that can be attached to and detached from the support body with a simple operation by a tool, but can be difficult to attach or remove without a tool. Provided.

A further embodiment of a filter device is disclosed in the dependent claims below 2 claims.

  When the end of the filter element is provided with a section that is not rotationally symmetric as a torque transmission mechanism, the torque is sufficiently transmitted by a suitably configured tool. The torque transmission mechanism can be designed as a protrusion or recess that is not rotationally symmetric with respect to the cylinder axis of the central tube. For example, a polygonal recess may be provided on the cover that closes the central tube, or a bead or protrusion may be provided on the cover that allows a screwing operation with a tool.

  An end disk having a tab-shaped recess having a torque transmission mechanism at the bottom may be provided at one end of the central tube. In this context, a tab-type recess is to be understood as a blind hole-type recess whose diameter is greater than the depth. The torque transmission mechanism can in particular be designed as a protrusion that rises from the bottom of the recess of the end disk, but is located below the upper rim of the end disk. The protrusion provided in the recess of the end disc functions as a means for transmitting the torque of a tool specially designed for it. Since these protrusions are provided in the recesses, it is not suitable for unscrewing or removing the air filter element by hand from the support body. In this way, it is possible to ensure that the air filter element cannot be removed from the support body without a special tool, or that it is always difficult to remove, preventing improper replacement of the air filter element. it can. The tab-shaped recess may be circular when viewed from above; this facilitates the use of the tool.

  The side surface of the protrusion may define a substantially right angle with respect to the bottom surface of the recess, that is, an angle of 75 to 105 degrees. Furthermore, the recess may be circular when viewed from above. The side surface of the protrusion may extend radially from the substantially recessed rim toward the cylinder axis of the central tube. Therefore, a large contact surface can be ensured between the special tool and the protrusion, and the special tool can be prevented from coming off from the protrusion.

  The air filter element can be provided with at least two protrusions, for example. Furthermore, these protrusions may be provided on opposite sides of the recess rim. As a result, a relatively short protrusion can be used as a means for transmitting the torque of the special tool; this makes it more difficult to remove the air filter element by hand.

  For example, the length of the side surface of the projecting portion extending in the radial direction may be less than half the radius of the recess. For example, the protrusions may be provided so as to be located on opposite sides of the rim of the recess. Thereby, torque can be efficiently transmitted to the air filter element.

  The end disk and the center tube can be configured as a single body. This makes it possible to produce a simple and inexpensive filter element that is not sealed separately, for example by injection molding.

This object is further solved by a filter housing having the features of claim 1 .

Accordingly, a filter housing is provided for housing the air filter element described above, the filter housing including a housing top part and a housing bottom part detachably coupled to the housing top part, wherein the housing bottom part Is provided with a cylindrical support body (21) , the support body having a filter-related fastening mechanism for the air filter element for attaching the air filter element to the end thereof facing the housing bottom part by insertion / rotation action; Interacting housing-related fastening means.

  The housing bottom part can be constructed as a unit with the support tube. This provides higher pressure resistance on the one hand and ensures improved operability during installation or removal on the other hand. Furthermore, the filter housing can therefore be manufactured in a simple and inexpensive manner.

  The cylindrical support body can be designed as an air permeable grid structure. This provides a relatively high stability support body, where a relatively large outer surface of the support body can be used for air flow through the filter.

  The two housing shells (housing top part and housing bottom part) can be held together, for example by a buckle or a removable screw connection.

  In one embodiment, to open the housing, the housing top part can be pivoted open about a pivot bearing located between the housing top part and the housing bottom part, thereby allowing the support pipe to open. It becomes accessible.

  In one embodiment, an air inlet opening for the cyclone filter stage is provided, in particular on the side of the housing top part and / or the housing bottom part. The cyclone filter stage is preferably integrated into one or more housing parts as a pre-separator. The cyclone filter stage is in particular formed by at least one in-line cyclone cell, which in-line cyclone cell has a pipe with a turning means on the inlet side for imparting rotational movement to the air flow, and a higher proportion of particles It includes a dip pipe on the outlet side for separating the flow area located radially outward, and a discharge opening for discharging the particles thus separated. The cyclone filter stage is particularly preferably arranged in such a way that the flow coming out of it flows past it without going directly to the filter element. In this way, a more uniform load on the filter element can be realized. More preferably, the flow exiting the cyclone filter stage can flow past the second filter element and can be fed into a housing wall positioned on the opposite side of the cyclone filter stage. This can also contribute to a more uniform inflow at the filter element, especially when only a minimal number of in-line cyclones are used as the cyclone filter stage.

This object is further solved by a filter device, in particular for portable handheld power tools . Such a filter device includes an air filter element as disclosed above that is mounted in the filter housing described above.

  In one embodiment of this filter device, the filter element is completely housed in the support body with a positive fit. In order to completely accommodate the filter element in the support body, the support body surrounds the filter element from the outside so that the upper end of the filter element is positioned below the upper edge of the support pipe. Therefore, since the upper end of the filter element does not protrude from the support pipe, the upper end of the filter element cannot be grasped by hand, and it is impossible or impossible to remove without any tools.

In a further embodiment of the filter device, a second cylindrical filter element is further provided. The second cylindrical filter element preferably has a filter bellows in which a fiber filter medium closed in a ring shape is folded in a zigzag shape. The support body is in particular the central tube of the second cylindrical filter element, so that radial support of the filter bellows on the inside can be ensured. As a result, a multi-stage filtration can be realized, where the second filter element preferably flows first from the outside (untreated side) to the inside (clean side) to filter the relatively large particles. And the first filter element as the auxiliary filter element functions to filter relatively small particles. In this connection, the first filter element can be fixed by an insertion / rotation operation. The second filter element can be configured to press fit into the support body. If the support body is the central tube of the second filter element (main filter element), this second filter element does not have to have its own central tube and can therefore be of a simpler construction. The second filter element may be designed to fit into the first filter element or the support body, i.e. it may be installed and removed without tools. Preferably, the second filter element has an end disk with an outflow opening and a seal that functions as a seal against the first filter element or the support body. This seal is preferably designed as a radial seal in an annular configuration and can engage the first filter element or the cylindrical sealing surface of the support body to separate the untreated side from the clean side. Furthermore, the second filter element preferably has a second closed end disk.

  Further possible embodiments of the invention include combinations not explicitly described of features or variations of the embodiments described above or below in connection with the embodiments. In this context, those skilled in the art will also add individual aspects as improvements or supplements to each basic form of the invention.

  The present invention will be described in further detail below with reference to the accompanying drawings and using specific embodiments as modifications. Each figure shows the following:

Perspective view of filter device Perspective view of filter element and bottom housing shell in which filter element is installed Sectional view of the filter element and housing shell of FIG. Connecting the filter element to the housing shell in detail Perspective view of bottom housing shell of filter housing Perspective view of bottom housing shell and main filter element of filter device

  In the figures, unless otherwise indicated, the same or functionally same elements are provided with the same reference signs.

The present invention will be described below using a filter for combustion air of an internal combustion engine, for example, an automobile. Corresponding filter elements are not designed to filter air, but can be designed to filter, for example, another gaseous medium, or even a liquid medium, such as oil .

  Below, the filter apparatus 1 containing the filter element 10 which concerns on one Embodiment is disclosed using FIGS. FIG. 1 is a perspective view of the filter device 1. FIG. 2 is a perspective view of the bottom housing shell 20a of the fluid tight housing 20 of the filter device in which the filter element 10 is installed. FIG. 3 is a sectional view of the filter element 10 and the housing shell 20a in FIG. FIG. 4 shows in detail the coupling of the filter element 10 with the housing shell 20a. FIG. 5 is a perspective view of the bottom housing shell 20 a of the filter housing 20.

  In this connection, it should be noted that the expressions “top” and “bottom” relate to the orientation in the figure and do not necessarily relate to the orientation of the filter device 1 in the mounted state.

The filter device 1 of this embodiment embodied as an air filter has a filter element 10 (see FIGS. 2 to 4) housed in a filter housing 20 of plastic material or the like. The filter housing 20 has a bottom housing shell 20a including a support tube 21 and an upper housing shell 20b.

  The two housing shells 20a and 20b can be held together by a buckle 22. When the buckle 22 is open, the housing shell 20b can be pivoted about the pivot bearing 23 provided at the upper end of the rear wall of the bottom housing shell 20a so that the housing shell 20b can be turned back, thereby allowing the support tube 21 to be accessed. It becomes. The filter element 10 is accommodated and fixed in the support tube 21 by the method described in detail below.

  An air inlet opening for the cyclone filter stage 25 is provided on the side of the upper housing shell 20b. The cyclone filter stage 25 is integrated into the upper housing shell 20b. The air that removes the particles by filtration is sent to the cyclone filter stage 25 through the air suction opening 24. In the cyclone filter stage 25, the particles are first separated from the air by cyclone separation. Particles may be removed through the discharge opening 26. The cyclone filter stage is formed in particular by at least one in-line cyclone, which comprises a pipe with turning means on the suction side for imparting rotational movement to the air flow and a radially outer side with a higher proportion of particles And a submerged pipe on the outlet side for separating the flow range located at the bottom. The cyclone filter stage is particularly preferably arranged in such a way that the flow coming out of it flows past it without going directly to the filter element. In this way, a more uniform load on the filter element can be realized. Further, the flow exiting the cyclone filter stage preferably flows past the second filter element and is fed into a housing wall positioned on the opposite side of the cyclone filter stage. This can also contribute to a more uniform inflow at the filter element, especially when only a minimal number of in-line cyclones are used as the cyclone filter stage.

The air thus preliminarily purified passes next through the filter element supplied to the support tube 21 and is purified by the filter material provided therein. The purified air finally leaves the housing from an air outlet socket 27 (see FIG. 4) at the bottom of the bottom housing shell 20a below the air permeable support tube 21. The purified air can be supplied to an internal combustion engine such as an automobile.

As can be seen in particular in FIG. 3, the filter element 10 includes a cylindrical central tube 11 whose outer surface is surrounded by a filter material 12 attached by a first seal 13 at the upper end of the central tube 11. Yes. The filter element 10 is fitted in the support tube 21. The support tube 21 is a cylindrical lattice-type support body, and is formed as a single unit with the bottom housing shell 20a. In this connection, the lower end of the support tube 21 is adjacent to the cup-shaped section of the bottom housing shell 20a which is formed at the bottom of the bottom housing shell 20a, so that the filter device 1 is provided with higher stability.

The center tube 11 has a fastening means for fastening the filter element 10 at the lower end thereof in the housing shell 20a. This fastening means in the filter is formed as a threaded portion 14 in the illustrated embodiment. A second seal 15 is disposed between the threaded portion 14 and the filter material 12. The filter fastening means interacts with the housing fastening means, thereby securing the filter element 10 to the support tube 21. More precisely, a threaded portion 29 is provided at the lower end of the support tube 21 in the housing. Therefore, the filter element 10 can be fixed to the support tube 21 by inserting and rotating. In this connection, the filter element 10 is first pushed axially into the support tube 21 until the filter-related thread 14 is resting on the housing-related thread 29. When the filter element 10 is rotated, the filter element 10 is screwed to the support tube 21. The threaded portions 14 and 29 should not be provided over the entire circumference of the central tube 11 or the support tube 21, but can also be formed as protrusions divided into several sections along the circumference. In particular, the threaded portions 14 and 29 may be formed so as to be fixed to the support tube 21 by rotating the filter element 10 by a relatively small angle, for example, an angle of 90 degrees or less or 45 degrees or less. In this way, the filter element 10 can be quickly fixed. The filter element 10 may also be fixed to the support tube 21 by means of a bayonet connection, a locking connection and / or a snap connection instead of the screw connection described above. Even in such a coupling, the filter element 10 is fixed to the support tube 21 only by the insertion operation.

  At the upper end of the central tube 11, an end disk 16 for hermetically closing the central tube 11 is provided. In the illustrated embodiment, the center tube 11 and end disk 16 are unitary, but it is also possible to provide the end disk as separate elements. The end disk 16 is provided with a tab-shaped recess 17, which in the illustrated embodiment is an inverted frustoconical shape. The end disk 16 has a first annular section 16a that extends adjacent to the cylinder wall of the central tube 11 and radially inwardly perpendicular thereto. The second annular section 16b is adjacent to the inner end of the annular section 16a and defines an angle of, for example, 110 to 160 degrees, for example about 135 degrees, with the first annular section 16a. The disc-shaped third section 16c is adjacent to the second section 16b and forms a recess 17 together with the second section 16b. The first seal 13 is also ring-shaped and secures the filter material 12 at the end of the central tube 11 by surrounding the first section 16a of the end disk and the end of the filter material 12 placed thereon. As the material of the first seal 13, polyurethane (PU) foam or PUR foam can be used.

  The air filter element 10 is provided with a torque transmission mechanism for transmitting torque from the tool to the air filter element. For this purpose, at least one protrusion 18 extending in the radial direction is provided at the inner rim of the recess 17, i.e. where the second section 16b intersects the third section 16c. In the illustrated embodiment, two protrusions 18a and 18b are provided as a torque transmission mechanism, from the rim of the recess 17 to a position approximately midway between the rim of the recess 17 and the center of the end disk 16. Extend. These protrusions 18 a and 18 b form a protrusion that protrudes from the bottom of the recess 17 to a height lower than the upper rim of the end disk 16. In the embodiment illustrated in FIG. 2, the two protrusions 18a and 18b are substantially parallelepiped and are positioned at opposite positions of the rim, i.e. offset by an angle of 180 degrees.

By using the protrusions 18a and 18b, the filter element 10 can be attached to or removed from the support tube 21. For mounting, the filter element 10 is pushed into the support tube 21 in the manner described above until the threaded portions 14 and 29 are placed on each other. As described above, the filter element 10 can be rotated and fixed with a special tool not disclosed in detail. For this purpose, a special tool is inserted into the recess 17 and turned so as to push the side surfaces of the protrusions 18a and 18b sideways. The protrusions 18 a and 18 b absorb the torque of the special tool and transmit the torque to the filter element 10. There are no restrictions on the construction of the special tool, except that it must be suitable for the transmission of torque to the protrusions 18a and 18b. For example, a rectangular blade similar to a screw driver may be provided at the end of the special tool. However, it is also possible for the shape of the special tool to match the recess 17, ie to have a truncated cone shape with a recess for the protrusion 18.

For example, in connection with maintenance, when the filter element 10 is released from the support tube 21, a special tool is also required for this purpose. In a state where the filter element 10 is completely accommodated in the support tube 21, the filter element 10 is surrounded by the lattice-type support tube 21, so that it cannot be gripped by hand or unscrewed. Further, there is no place on the upper end that can be used to transmit torque to the filter element 10 without a tool. Therefore, the filter element 10 cannot be fixed to the support tube 21 by hand, or cannot be released from the support tube 21, or it is always difficult to fix and release. This ensures proper replacement of the filter element 10 since the required special tools are generally only available to authorized repair shops or distributors or maintenance personnel with proper authorization or training.

  The side surface of the protrusion 18 defines an angle of, for example, 75 to 105 degrees, preferably substantially 90 degrees with respect to the bottom surface of the recess. A side surface of the protrusion 18 extends in a substantially radial direction from the rim of the recess 17 toward the cylinder axis of the central tube 11. Therefore, a large contact surface can be ensured between the special tool and the protrusion 18, and the special tool is prevented from falling off from the protrusion 18. Furthermore, by providing the protrusion 18 on the rim of the recess, i.e. as far as possible from the axis of rotation, efficient torque transmission is ensured.

The filter housing 20 of this embodiment can be opened and closed without tools. In this connection, the closure with the buckle can be quickly operated with one hand. Since the support tube 21 has a lattice structure and extends to the end of the filter element 10, as described above, the filter element 10 cannot be mounted or removed without a tool. Therefore, special tools for mounting and removing the filter element 10 are required; this ensures correct maintenance work. However, since the filter housing 20 can be opened with one hand and the filter element 10 can be fixed with only a simple insertion operation or with an insertion and rotation operation , this can be done with a few operations.

  In the illustrated embodiment, two protrusions 18 are provided, but it is also possible to have more than two protrusions 18. It is also possible to have only a continuous protrusion extending from the rim on one side of the recess 17 through the center of the end disk 16 to the opposite side of the rim. Furthermore, it is also possible to have two protrusions 18a and 18b that are not opposite to each other and that form an angle of 90 degrees along the rim of the recess 17, for example. This requires specially configured special tools and is prevented from being replaced by a single rectangular blade or the like.

  The filter device 1 including the filter housing 20 and the filter element 10 achieves two-stage filtration by a cyclone pre-filtration action by the cyclone filter stage 25 and a main filtration action by the filter element 10. However, it is also possible to have a larger number of filter stages. Such a filter device 50 is schematically shown in FIG.

The filter device 50 according to this embodiment includes the above-described filter housing 20, an auxiliary filter element not shown in further detail, and a main filter element 60. The filter element 10 described above can be used as an auxiliary filter element, and therefore the aspects of the filter housing 20 and the filter element 10 already discussed in this connection will not be described again. FIG. 6 shows only the second filter element 60 pressed into the bottom housing shell 20 a of the filter housing 20 and the air permeable cylindrical support tube 21.

In the illustrated configuration, the filter element 60 functions as the main filter element of the filter device 50 including the main filter element 60 and the auxiliary filter element. The main filter element 60 is also a cylindrical, includes was enclosed in the filter material 61, the cylinder-shaped lattice-type central tube which is not shown in detail. At the end of the central tube is provided an end disk 62 of polyurethane (PU) or PUR foam, which hermetically closes the cylindrical central tube.

  The filter material 61 of the main filter element 60 is designed to filter out larger particles from the air, and the filter material of the auxiliary filter element is designed to filter out finer particles.

After pre-filtration by the cyclone filter stage 25, the air to be filtered passes through the filter material 61 of the main filter element 60, passes through the support tube 21, and then passes through the filter material of the auxiliary filter element, It is guided out through an air discharge opening in the bottom of the bottom housing shell 20a. As a result, three-stage filtration is provided.

The main filter element 60 can be pushed into and removed from the support tube 21 by a simple operation by hand, so that the replacement can be done quickly and easily. In this connection, since the auxiliary filter element is constructed as described above, it is ensured that a special tool is required to completely replace the filter device, thus ensuring correct maintenance.

In an advantageous embodiment, the support tube 21 can simultaneously function as the central pipe of the main filter element 60. Thus, additional components can be avoided, which makes it possible to implement the filter device more cost-effectively.

The above-described embodiments should be understood as exemplary embodiments only, and other configurations that are also intended to be included in the scope of protection may be considered. For example, the torque transmission mechanism may also be provided on the end disk as a polygonal recess having no rotational symmetry. Furthermore, it is possible to provide the end disk with several recesses as a torque transmission mechanism. Furthermore, the torque transmission mechanism can be designed as one or more protrusions that do not have rotational symmetry on the end disk. These or other geometric configurations can also ensure that the torque transmission mechanism interacts with the tool according to the key and keyhole principle and cannot or cannot be installed without the tool. .

Claims (8)

An air filter element (10) formed by surrounding the outer surface of a cylindrical central tube (11) with a filter material (12);
A filter housing (20) for housing the air filter element (10), comprising an upper housing part (20b) and a bottom housing part (20a) removably coupled to the upper housing part (20b); ,
An air-permeable cylindrical support body (21) that is fitted to the outer periphery of the air filter element (10) and supports the air filter element (10);
Torque transmitting unit for provided in the cylinder axis direction end, for transmitting torque from the specially designed special tools on the air filter element (10) of said central tube (11) and (18),
Wherein provided on the other end of the central tube (11), the fastening portion for mounting detachably on the air filter element (10) the inserting operation only or inserted and said cylindrical support body by rotation (21) (14 29 ), and a filter device (40) . The torque transmitting portion (18), said central tube (11) wherein are formed as protrusions or recesses having no rotational symmetry with respect to the cylinder axis of the filter device according to claim 1 (40). The filter device ( 1) according to claim 1 or 2, comprising an end disk (16) having a tab-shaped recess (17) provided with the torque transmission part (18) at the bottom at one end of the central tube (11). 40) . The filter device (40) according to claim 2 , wherein the torque transmitting part (18) has at least two protrusions positioned on opposite sides of the rim of the recess (17 ) . The filter device (40) according to claim 3 , wherein the end disk (16) and the central tube (11) are formed as a single unit. The filter device (40) according to claim 1 , wherein the cylindrical support body (21) is formed as an air permeable grid. The filter device (40) according to claim 1 , wherein the air filter element (10) is completely and positively accommodated in the cylindrical support body (21). Further comprising a second air filter element (60) which the outer surface is formed surrounding the second filter material (61) of said cylindrical support body (21), said cylindrical support body (21), said first 2. A filter device (40) according to claim 1 , formed as a second central tube of two air filter elements (60).

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